Patent · US Expired

Perpendicular magnetic recording medium

US4923763A · kind A · utility

2Cited by
6References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1988
Grant dateMay 8, 1990
Priority date
Expiry dateSep 19, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31725
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

There are disclosed a perpendicular magnetic recording medium comprising a substrate of a polymer film containing 0.7% by weight or less of a residual solvent and a ferromagnetic alloy layer formed on the substrate and a method for preparing the same comprising the steps of heating a substrate composed of a polymer film containing a residual solvent in order to regulate a content of the solvent existing in the substrate to 0.7% by weight or less; and afterward forming a magnetic layer composed of a ferromagnetic alloy on the substrate. The perpendicular magnetic recording medium of the present invention has a prolonged durability and heightened reliability.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.